1. Field of the Invention
This invention relates to the field of cables and ropes. More specifically, the invention comprises a process for thoroughly infusing liquid potting compound into the strands of a rope or cable in order to affix an anchor.
2. Description of the Related Art
Devices for mounting a termination on the end of a rope or cable are disclosed in detail in U.S. Pat. No. 7,237,336 to Campbell, which is incorporated herein by reference. Throughout this disclosure, the term “strand” will be used to describe the constituents of synthetic cables, natural-fiber cables, and ropes. Although synthetic cables are used for the illustrations, the reader should understand that the methods and devices disclosed are equally applicable to any type of stranded cable.
It is often useful to affix a piece of hardware to the end of a cable. Examples of hardware would be threaded fasteners, hooks, and eyes. Such hardware will be generically referred to as an “anchor.” Anchors typically have an expanding internal passage or some type of interlocking features, such as ridges. The strands proximate the end of a cable are wetted with liquid potting compound. The wetted strands are then placed within the internal passage of the anchor. The potting compound then hardens to form a solid, thereby locking a length of strands into the anchor. The anchor, along with the contained strands and solid potting compound will be referred to as a “termination.”
Those skilled in the art will know that the term “potting compound” generally refers to any liquid which can be transformed into a solid (such as by air-drying, cooling, reacting with a catalyst, etc.). Examples include thermoplastics, molten metals, thermosets, and reactive compounds (such as two-part epoxies).
Two methods of infusing liquid potting compound into the strands of a cable are in common use. These are: (1) Pulling an anchor into its final position around the exposed strands and pouring the liquid potting compound into an open end of the anchor; or (2) Infusing the exposed strands with liquid potting compound, then pulling the anchor into its final position (The infusion is typically accomplished via painting on the liquid potting compound or dipping the exposed strands into a vat of liquid potting compound).
Under either approach, the potting compound may fail to fully infuse the strands. Moreover, both approaches must generally be performed manually, resulting in drastic variations from termination to termination.
FIG. 1 shows four cables 10 with exposed strands in varying configurations. The far left example shows core strands 12 exposed and ready for potting in an undisturbed state. Proceeding to the right, the next example shows the exposed strands being compressed to form fanned strands 14. The next example shows the exposed strands being splayed to form conical strands 16. The far right example shows the strands being splayed apart further to form radially fanned strands 44. All these examples, as well as others, may be employed prior to infusing the exposed strands with liquid potting compound. However, as the infusion is carried out manually, all these methods are susceptible to unwanted inconsistencies. The present invention proposes a method for producing a consistent and repeatable cable termination.